2006 Summers of Discovery Intern Anirudh Kota has one of the best reasons ever to miss school next month. The Cary Academy junior and his chemistry teacher/mentor, Katy Allen, will spend March 26 and 27 in Charlotte. They will attend a workshop on "K-12 Education: Investing in the Future of Toxicology" and Kota will participate in the poster session at the Society of Toxicology Annual Meeting and ToxExpo.

The poster session will feature a study that scientists working with Neurotoxicity Group Director Jean Harry, Ph.D., conducted in the NIEHS Laboratory of Neurobiology. Kota was principal investigator on the study, titled "Comparison of injury-induced neurogenesis in young and aged mice." Harry served as corresponding author on the study, and Graduate Student/Technician Chris McPherson and Visiting Fellow Mineyoshi Aoyama, M.D., Ph.D., worked with Kota and Harry as co-investigators.

Near the end of his internship, Kota was a winner in the Summers of Discovery poster session. Last fall, the Science Day Awards committee invited the young scholar to return for the annual NIEHS event. His abstract appeared among the rows of abstracts by post-doctoral fellows displayed in the lobby outside Rodbell Auditorium, and, like his older, credentialed colleagues, Kota answered questions about his work from NIEHS scientists, visitors and judges.

Kota began his summer at NIEHS with the basics, learning how to slice, stain and photograph, reading the studies that Harry sent his way and mastering the lexicon of laboratory science and toxicology. According to McPherson, often Kota was able to complete his learning assignments in half the time expected. "He picked up things quickly, and he kept coming back for more work," commented McPherson. "We kept giving him more responsibility, and we probably could have given him even more."

For the young chemist, getting the internship at NIEHS was a dream come true. "I was surprised when I went in for the interview and Jean did not even know she had spots, but she said up front, 'If I have a spot, it is yours.' I was very surprised and ecstatic. When I got home, I started jumping up and down like I'd gone crazy."

Both of Kota's parents work in scientific careers, his mother as a computer engineer and his father as a pharmacist, and they have encouraged his interest in science. Over the years, their son developed a love for chemistry and plans to pursue a career that involves working in that field. For his next move after high school, he's considering Duke and the University of North Carolina at Chapel Hill, and he's also looking into the seven-year medical program at East Carolina University.

Back at Cary Academy after his summer at NIEHS, Kota is taking Advanced Placement Chemistry and pursuing his several additional interests. Along with maintaining a high grade point average and making the honor roll, he is an enthusiastic athlete, excelling in basketball and soccer, an avid reader and an award-winning debater in tournaments sponsored by the National Forensics League.

Harry and Kota's colleagues at NIEHS were very pleased with the quality of his work - and even more importantly, with his attitude. Kota impressed his supervisor as being "very pleasant to work with, very responsible and very interested in what he was doing," Harry observed. "[Anirudh] seemed to be doing it [Summers of Discovery Research] more because he was interested in learning than in doing it for something to put on an application to college."

When it comes to the summer of 2007, Kota doesn't have set plans yet. He'd like to return to NIEHS if the program will let him, and Harry would like to have him back. "He was outstanding," Harry concluded. "He asked good questions and wanted to do things right, not just impress people."

Recent work has identified proliferation of new neurons as a common feature of the adult brain. Neurogenic sites include both the subventricular zone and the subgranular layer/zone (SGZ) of the dentate gyrus (DG) as sources of stem cells and progenitor cells. While neurogenesis occurs at a low basal level in the normal brain, the generation of new cells can be stimulated by both synaptic activity and injury. This process declines as a normal process of aging. In the current study, we examined the level of neurogenesis within the SGZ both under normal basal conditions and following a focal injury to the neurons of the dentate gyrus. Using this model, we compared the level of neurogenesis in weanling mice (21-days-old) with the process occurring in the aged mouse brain (1 yr old). Mice received an acute ip injection of the hippocampal toxicant, trimethyltin (TMT) followed by bromodeoxyuridine (BrdU) at 50 mg/kg/bid/ip for 3 days. The level of neurogenesis was examined histologically and the differentiation of newly generated cells was identified by co-immunofluorescent staining with markers for neurons (NeuN). While injury induced neurogenesis and the differentiation to mature neurons occurred in the aged brain, it was significantly decreased as compared to the young. The distribution pattern of the new neurons within the dentate gyrus was also slightly altered over this time period. Using this model, we will continue to examine the differentiation of new cells to other cells types and by comparison as a function of aging.

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